AT&T MMS requires iPhone OS 3.1 and a carrier settings update. Use these steps to update your iPhone to the latest iPhone OS and carrier settings:
- Make sure that you have a working Internet connection on your computer and that you are using iTunes 8.2 or later.
- Connect iPhone to the computer and open iTunes.
- Select your iPhone in the Devices list and click "Check for Update".
- Update to iPhone OS 3.1 if prompted to do so.
- Click "Update Settings" when prompted.
- When the update is complete, you will see the following screen:
- Restart your iPhone.
- Hold the power button until "slide to power off" appears. Slide to power off your device. When it is off, press the power button to turn it back on.
After iPhone restarts, verify MMS is active by creating a new text message. You should see the camera icon to the left of the text field:
For more information on using MMS, see the iPhone User Guide.